The ATP11A Knockout HAP1 Polyclonal Cells consist of a heterogeneous population of human HAP1 cells carrying CRISPR/Cas9-mediated disruptions in the ATP11A gene, serving as a loss-of-function model for investigating P4-ATPase flippase biology. This polyclonal knockout pool avoids clonal selection while providing robust gene-editing outcomes. The model harnesses the well-characterized HAP1 cell line, enabling detailed studies of ATP11A-dependent phospholipid transport and its downstream effects.
The host HAP1 cell line is a near-haploid chronic myelogenous leukemia (CML) cell line with adherent fibroblastoid morphology, derived from the myeloid lineage. Its near-haploid karyotype simplifies genetic manipulation and facilitates clear phenotypic interpretation, making it widely adopted for functional genomics and CRISPR screens. Retaining core leukemic signaling networks, HAP1 is particularly suited for dissecting genes involved in cell proliferation, apoptosis, and membrane dynamics.
ATP11A encodes a P4-ATPase flippase that, together with its obligatory chaperone TMEM30A, actively translocates phosphatidylserine (PS) and phosphatidylethanolamine from the outer to the inner plasma membrane leaflet, preserving lipid asymmetry. This activity is regulated by calcium influx and phosphorylation by protein kinase C (PKC). Inactivation of ATP11A disrupts flippase activity, causing PS externalization??an ‘eat-me’ signal for phagocytes and a hallmark of apoptosis. This event can activate downstream AKT/PKB and PKC pathways, promote caspase-dependent apoptosis, and potentially engage Bcl-2 family proteins, thereby linking membrane phospholipid dynamics to cell fate decisions. Additional interactions with calnexin for quality control underscore the complexity of ATP11A regulation.
In the HAP1 background, the single allele knockout of ATP11A ensures uniform loss of flippase function across the polyclonal population, leading to consistent PS scrambling. This disruption triggers pro-apoptotic and pro-coagulant signals, making the cells a potent model for studying phosphatidylserine-mediated signaling in myeloid leukemia, thrombosis, and developmental disorders like leukoencephalopathy. The near-haploid nature amplifies the phenotypic consequences, offering a clear readout of lipid asymmetry imbalance.
These polyclonal knockout cells are ideally applied in apoptosis assays (caspase-3/7 activation, Annexin V flow cytometry), phospholipid flippase activity assays using fluorescent substrates, and signaling analysis (e.g., AKT phosphorylation). They also support drug screening for flippase modulators and research into CML biology. For additional inquiries, please contact Ascent Research.
